Speaking with others via a handset device raises privacy concerns. If a user speaks into the handset device at a normal volume in a crowded area, for example, unintended listeners may hear the user's conversation. This is especially problematic if the user is communicating private information. In such a case, a user may speak quietly into the handset device. Generally such quiet speech leads to a low signal-to-noise ratio (“SNR”) and a muffled profile in the resulting acoustic signal, making it difficult for the intended recipient to hear.
Various techniques have been aimed at solving this problem. For example, amplification or automatic gain control techniques may be used to increase the signal's volume. While this may make the signal easier to hear, it does little to remove noise from the signal or to smooth the profile of the signal. As such, the resulting signal is still difficult for the intended recipient to understand.
The limitations of previous approaches have resulted in some user dissatisfaction with these previous approaches.